The present invention relates to a system including a replaceable cartridge comprising replaceable wheel members.
The present invention is hereinafter disclosed with reference to a document encoding machine where documents are taken from a stack and fed into a track. The invention is not restricted to such an application. The invention may be used in any circumstances where two or more wheels and/or a belt can be removed and replaced.
Document encoding equipment operates upon bankers checks and other like documents to gain printed or magnetic data from the documents and to apply coded marks to the documents for their later machine processing. Before any action can be taken upon the documents, the documents must first be fed into a document track, along which lie various sensors, document readers and document printers. The documents are fed into the track from a stack. An elastically faced drive wheel and drive belts urge documents from the stack between the drive wheel and a scrub wheel one-by-one into the track. The scrub wheel and driven wheel rotate at different speeds and consequently the surfaces abrade against one another. The slow mutual attrition between the drive wheel and the scrub wheel means that both of these items require periodic replacement. Likewise the belts associated with the drive wheel also require replacement as they stretch and become unserviceable.
The act of replacing the drive wheel and/or the drive belts can be time consuming. Before the drive wheel can be removed, tension in the drive belts must be released, the drive belts removed from the drive wheel and the drive wheel released from its mounting shaft. Since one drive belt is provided at the base of the drive wheel and another at the top of the drive wheel, in order to remove and change the drive belts, it is necessary to maneuver the bottom drive belt all the way up the drive wheel assembly before it can be removed. The changing of the belts or drive wheel requires skilled service personnel using tools and both hands. The present invention seks to provide improvement through use of a replaceable cartridge system allowing rapid one-handed changeover by personnel who are not required to be skilled and without the use of the tools.
SUMMARY OF THE INVENTION
The present invention consists in a system including a replaceable cartridge and a base for receiving the cartridge; said cartridge including a plurality of replaceable wheel members; said base including a plurality of bearing members, one for each of said plurality of wheel members, each permitting the rotation of its respective wheel member there-about; said cartridge including a central carcass, having a plurality of recesses, there being one recess for each of said plurality of wheel members: and an elastic belt passing around the outside of said carcass; said belt being operative to retain each of said plurality of wheel members in its respective recess when said cartridge is not on said base; where, when said cartridge is engaged with said base, said carcass is located on said base such that each of said plurality of bearing members co-operates with its respective wheel member to space said wheel members away from said carcass.
In a preferred embodiment of the invention, the cartridge comprises a drive wheel, a first idler wheel, a second idler wheel and first and second drive belts passing around the carcass, around the drive wheel and being supported by the first and second idler wheels. The belts co-operate with the idler wheels and the drive wheel when the cartridge is not mounted on a base to retain the idler wheels and the drive wheel in recesses on the cartridge.
In the preferred embodiment there is provided a base having first and second idler pins and a feed hub assembly. When the drive wheel is located upon the feed hub assembly the first and second idler wheels respectively self-locate upon the first and second idler pins. The carcass locates upon first and second carcass locating pins on the base.
Also in the preferred embodiment the feed hub assembly and the drive wheel co-operate to provide a self-gripping, push button ejection holding means for retaining the drive wheel on the feed hub assembly. The preferred embodiment also provides that the first and second idler pins and at least one of the carcass locating pins is mounted upon a movable plate over a baseplate whereon the feed hub assembly is fixed. A tensioning lever located on the baseplate is moved from an open to a closed position for activating a cam mechanism to move the movable plate so that the belts are tensioned with the drive wheel and idler wheels free from the recesses in the carcass.